Integral image elements which use a lenticular lens sheet or a fly's eye lens sheet, and a three-dimensional integral image aligned with the sheet, so that a user can view the three-dimensional image without any special glasses or other equipment, are known. Such imaging elements and their construction, are described in "Three-Dimensional Imaging Techniques" by Takanori Okoshi, Academic Press, Inc., New York, 1976. Integral image elements having a lenticular lens sheet (that is, a sheet with a plurality of adjacent, parallel, elongated, and partially cylindrical lenses) are also described in the following U.S. Pat. Nos.: 5,391,254; 5,424,533; 5,241,608; 5,455,689; 5,276,478; 5,391,254; 5,424,533 and others; as well as allowed U.S. patent application Ser. No. 07/931,744. Use of barrier viewing sheets having alternating opaque and transparent lines, instead of a lenticular lens sheet, is also well known.
Integral image elements with lenticular lens sheets use interlaced vertical image slices which, in the case of a three-dimensional integral image, are aligned with the lenticules so that a three-dimensional image is viewable when the lenticules are vertically oriented with respect to a viewer's eyes. Similar integral image elements, such as described in U.S. Pat. Nos. 3,268,238 and 3,538,632, can be used to convey a number of individual two-dimensional scenes (such as unrelated scenes or a sequence of scenes depicting motion) rather than one or more three-dimensional images. Such elements then, when tilted through a range of angles with respect to a viewer's eyes (by moving the element and/or the viewer's eyes), can display different images (whether different perspectives of the same scene) and/or unrelated images, and/or a sequence of images depicting a motion sequence of events. With improvements in technology, the effects obtained can be startling.
Integral image elements using reflective layers behind the integral image to enhance viewing of the integral image by reflected light, are also described in U.S. Pat. No. 3,751,258, 2,500,511, 2,039,648, 1,918,705 and GB 492,186.
In a typical method of assembling a lenticular type of integral image element, an original negative is exposed from stored digitized data of a composite lenticular image on a film writer. A suitable film writer is the Symbolic Sciences International Fire 1000 and the LVT Model 1620B, available from Light Valve Technology, a subsidiary of Eastman Kodak Company, Rochester, N.Y. A suitable negative exposure technique is disclosed in U.S. Pat. No. 5,276,478. After photographic processing, the negative is printed, typically by a projection enlarger, onto a suitable film- or paper-based photographic print stock. After processing, the lenticular composite print is coated with adhesive, aligned with a lenticular lens sheet, and pressed against the lens sheet to permanently adhere to it in proper registration with the printed lenticular composite image. However, it is also known to write the lenticular image directly onto a back side of a lenticular lens sheet which is coated with a suitable receiving layer, such as disclosed in U.S. Pat. Nos. 5,349,419 and 5,279,912. Furthermore, such "writing" of the lenticular image can be temporary, as in a display produced on a CRT or Liquid Crystal Display ("LCD") screen immediately adjacent the back side.
One difficulty with lenticular images though, occurs when one image of the lenticular image is substantially different in content than the next. For example, when the lenticular image is composed of a motion sequence, the first and last images in the sequence will be considerably different in content with respect to the one or more elements in the image scene which are in motion. As the image element is tilted through a range of angles to observe the images of lenticular image (such as the motion sequence), an undesirable jumping takes place between such images of substantially different content For example, in the case of a lenticular image carrying a single motion sequence, during tilting of the image element through a range of angles to observe the motion sequence, a sudden jumping will be observed between the last and first images of the motion sequence as the angle is increased beyond the primary viewing angle of the images. Such jumping can be very distracting from the viewer's enjoyment of the content of the lenticular image itself. Further, because of this jumping viewers often have problems in seeing all the images and understanding their logical succession, as in the case of a lenticular motion sequence.
Thus, it would be highly desirable to provide viewers with lenticular images with a means which reduces or eliminates such distracting jumping and the resulting problems.